Ah yes, you don't have the correct URL. Need a URL to the actual file. Alas Google Docs/Drive doesnt make ti easy.
Given your URL
which will redirect to
for some people (it just did for me)
Whereas you need a url like
(note the /uc at the start and export=download on the end)
The only way I know to build them is manually. But you can do quite easily for other files, as notice the long ID is the same in all version of URLS>
> We are also wondering how we can set the default orientation of the globe when it is first viewed in the gadget from our website?
Can do this with the 'snapshot view' feature in Google Earth, when creating the KML in the firstplace. So use the snapshot view option on the top most element you saving. Then save it as a kml/kmz file.
The plugin will honour that view.
> Where might there be instructions on creating your own custom icons or placemarkers?
mentions this - also mentions snapshot view!
> Can custom placemarkers also be shown on a 2-D Google map of the world?
Yes. But have to be careful. Google Maps will usually resize icons to 32x32px. So best to start with icons already in those dimensions.